This is how Jenkins jobs launch the VM. This is different from the above provisioning workflow. Rather than getting an interactive shell directly from Qemu, we we launch the Qemu with an SSH port exposed, and login that way:

Before publishing a new snaphot, verify that you are able to launch the VM and connect to it over SSH using the "Launch for remote control" steps above.

Use sudo to move the img file from your home directory to /srv/vm-images/qemu-<flavour>-<date><sequence>.img. For example, /srv/vm-images/qemu-debian10buster-2020_04_28a.img, or …-2020_04_28b.img, where the sequence letter is used in case of multiple updates on the same date.

Set chmod 644 *.img, so that it is available as read-only for the Jenkins user.